<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>主页</title>

    <link rel="stylesheet" href="//unpkg.com/layui@2.6.8/dist/css/layui.css">

</head>
<body>
    <div class="layui-col-md3" style="background-color: aquamarine">
        你的内容 3/12
    </div>
    <div class="layui-col-md6">
        sasaa
    </div>
    <div class="layui-col-md3" style="background-color: aquamarine">
        你的内容 3/12
    </div>

</body>
<script src="//unpkg.com/layui@2.6.8/dist/layui.js"></script>
</html>